Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description discloses key behavioral details beyond the annotations: Solentic polls every 60 seconds and POSTs to the URL when events fire. This adds meaningful context about the delivery mechanism. It does not cover error handling, idempotency, or duplicate registration, so it isn't fully transparent, but it's well above the minimum.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is exceptionally concise: two sentences, front-loaded with purpose, and every phrase contributes (events, polling interval, POST method). No unnecessary wording or repetition. It is a model of efficient writing.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a tool with four parameters and no output schema, the description provides the essential semantic information: what events exist and how notifications are delivered. It doesn't explain the return value or how registration interacts with existing webhooks, but that's partially covered by sibling tools and the schema. Good overall coverage.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, giving the baseline of 3. The description adds significant value by explaining each event enum value (e.g., 'withdraw_ready (stake account becomes withdrawable)'), which helps the agent choose appropriate event subscriptions. This goes beyond the raw schema and justifies a 4.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Register a callback URL') and resource ('to receive push notifications when stake state changes'). It distinguishes itself from sibling tools like delete_webhook and list_webhooks by explicitly being the registration operation. The event list adds specificity and depth.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides clear context on when to use the tool: when push notifications for stake state changes are needed. However, it does not explicitly mention alternatives or when not to use it, such as using list_webhooks to view existing subscriptions or delete_webhook for removal. This falls short of a full 5.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.